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3 years ago

2. In which phase will crossing-over occur?

Biology

1 answer:

Strike441 [17]3 years ago

8 0

Crossing over occurs in; Meiosis, Prophase I.

The events that take place in phase, Prophase I are:

Each set of sister chromatids pair up with its homologous pair of chromosomes, forming a set of four chromatids.

• At several places along their length, non-sister chromatids (chromatids that belong to homologous chromosomes but are not identical sister chromatids) undergo a process called crossing over.

• The chromatids of homologous chromosomes cross over one another to hold the set of four chromatids together. Then the crossed sections of the chromatids are exchanged, forming new combinations of alleles in the cell.

• As prophase I continues, the cell prepares for a division of the nucleus like what happens in mitosis.

• Spindle fibers form between the centrioles, which are at opposite ends of the cell.

• The nuclear membrane and the nucleolus disappear.

<em>Prophase I is the longest stage of meiosis, often taking up to 90% of the time required for the entire process to occur. </em>

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Arrange the events taking place during transcription in order: i) The pre-RNA undergoes processing ii) RNA polymerase moves down

Anastasy [175]

Answer:

RNA polymerase binds to the promoter

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The pre-RNA undergoes processing

Explanation:

The promoter is the specific DNA sequence that serves as a binding site for RNA polymerase. The enzyme RNA polymerase recognizes the promoter sequence and binds to it to begin the process of RNA synthesis. The process of RNA synthesis begins at the start site where the process of the unwinding of DNA duplex is initiated.

The unwinding separates the two DNA strands at the start site where RNA polymerase begins the process of synthesis of the new RNA strand. The newly formed RNA strand and RNA polymerase are released from the template strand after the termination of the process.

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3 years ago

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Answer:

The correct answer will be- Elevation

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The movement of the muscles attached to the skeleton system allows the movement of the body parts.

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Thus, Elevation is the correct answer.

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